Production of High Purity Magnesium Alloys by Melt Purification with Zr


  • The research on Mg corrosion, flammability, and stress corrosion cracking is supported by Boeing Research and Technology, CAST CRC, the Australian Research Council Centre of Excellence Design of Light Alloys, and GM Global Research and Development. CAST CRC was established under, and is funded in part by the Australian Federal Government's Cooperative Research Centre scheme. Support is gratefully acknowledged of Donald S Shih and of Boeing Research & Technology, St Louis, Missouri, USA.


The efficacy of Zr in removing Fe from molten Mg-X binary alloys was studied experimentally and using calculated phase diagrams. Zr is effective in reducing the Fe content from the Mg melt for Mg-X binary alloys, X = Y, Si, Sn, Ca, Sr, Ce, Gd, Nd, Li, La, Mn, and Zn. Purification occurs by the precipitation from the melt of Fe rich precipitates, and the settling of the precipitates to the bottom of the melt. Any desired Fe content down to 1 ppm can be achieved by appropriate melt treatment.